Observational findings regarding differentiated child behavior in Follow Through classrooms for the year 1971 are presented. The interactional behavior of three groups of elementary school children from different classroom settings (Bank Street School for Children, an open classroom approach; Bank Street Follow Through, an open classroom approach; non-Follow Through, traditional classroom approach) was observed using the Differentiated Child Behavior Observation System (DCB). This instrument is used for recording in quantifiable form selected attributes of children's classroom interaction such as: gives information, asks questions, expresses, acts destructively, organizes and manages, represents and symbolizes. It also provides a means for coding both interactional and substantive aspects of classroom behavior. The results of the study showed the Follow Through classroom to be a more active classroom setting than non-Follow Through Classrooms. (MLP)